1. Field of the Invention
The present invention relates to liquid crystal display (LCD) devices, and more particularly, to a bracket for an LCD device and to a method of assembling a LCD device having the bracket.
2. Background of the Related Art
Cathode Ray Tubes (CRT) are typically used in measuring instruments, and monitors, such as televisions. However, the weight and size of CRTs do not make them practical for small, light weight devices.
Therefore, LCD displays having an electro-optical effect applied thereto, Plasma Display Panels (PDP) having a gas discharge applied thereto, and Electro Luminescence Displays (ELD) having an electro luminescence applied thereto have been developed to address the shortcomings of CRTs.
Of the aforementioned displays, LCDs are the most widely used due to their good visibility, low average power consumption, and low heat generation compared to a same sized CRT.
However, as the LCD is a non-emissive type display device which does not emit light, a separate external light source is required. In some instances, an ambient natural light may be used. However, the environment in which the LCD operates may impose many limitations on the device, thereby making the use of ambient light impractical. Accordingly, an independent light source is provided.
Typically, this type of independent light source is called back light unit. Commonly, the back light unit employs an Electro Luminescence (EL) device, Light Emitting Diode (LED), Cold Cathode Fluorescent Lamp (CCFL), Hot Cathode Fluorescent Lamp (HCFL), or the like as the light source.
However, a voltage higher than 2000V is required for driving a CCFL. Thus, a device employing a CCFL requires an inverter for converting a DC voltage and boosting the voltage enough to drive the CCFL.
A related art LCD and a bracket thereof will be described with reference to FIG. 1 which illustrates a perspective view of a related art LCD.
Referring to FIG. 1, a related art LCD is provided with a liquid crystal display panel 10, a top case 70 on the liquid crystal display panel 10, and a back light assembly under the liquid crystal display panel 10. The back light assembly projects light through a back surface of the liquid crystal display panel 10.
The liquid crystal display panel 10 has liquid crystals injected between a pair of substrates for displaying a picture. The top case 70 encloses the liquid crystal display panel 10 and the back light assembly.
The back light assembly includes a support frame 30, a bottom cover 40, and a lamp 60 for projecting light through the back of the liquid crystal display panel 10.
The support frame 30, which is located at the under side of the liquid crystal panel 10, has a space for receiving and holding the liquid crystal panel 10 and the lamp 60. The bottom cover 40, located at the bottom of the support frame 30, protects the lamp 60 and prevents light leakage. In general, the support frame 30 is formed of plastic, and the bottom cover 40 is formed of a metal with a thermal conductivity better than plastic, such as aluminum.
In addition, the LCD in FIG. 1 has a light guide plate 52 at a side of the lamp 60 for providing uniform light illumination of the liquid crystal display panel 10.
The back light assembly will now be described.
The light guide plate 52 at the side of the lamp 60 directs light from the lamp 60 toward the LCD display panel 10 uniformly. A reflective plate 50 under the light guide plate 52 reflects light leaking in a direction opposite to the liquid crystal display panel 10 toward the light guide plate 52.
Optical sheets 54, such as a diffuser sheet, a prism sheet, and a protection sheet are disposed on the light guide plate 52 in succession. The diffuser sheet diffuses light from the light guide plate 52 thereby uniformly diffusing light. The prism sheet converges the light diffused at the diffuser sheet. The protection sheet protects the prism sheet, and uniformly diffuses any incident light.
In general, one lamp 60 is needed with a small sized liquid crystal display device at the side of the light guide plate 52. However, larger liquid crystal display devices require at least two lamps 60 mounted at the side of the light guide plate for adequate luminance.
Furthermore, the top case 70 also includes a bracket 80 for fastening an inverter 90 thereto that supplies power to the lamp 60.
FIG. 2 illustrates a perspective view of a related art bracket.
Referring to FIG. 2, the related art bracket 80 includes a fourth plate 81 having screw holes 81a formed therein, and first and fifth plates 82 and 83. The fourth and fifth plates 81, 83 extend in the same direction from opposite edges of the first plate 82.
A width of the ends of the fourth plate 81 are smaller than a width of a middle portion of the fourth plate 81. The fourth plate 81 also has a plurality of screw holes 81a that facilitate fastening with the top case 70.
The first plate 82 is bent perpendicular relative to the fourth plate 81 from the middle section of the fourth plate 81. Additionally, the fifth plate 83 is bent perpendicular relative to the first plate 82 from a middle section of the first plate 82 such that the fourth plate 81 and the fifth plate 83 are parallel to each other.
In addition, the fourth plate 81 has a fastening part comprising a second plate 84 which extends from one end of the fourth plate 81. In addition, the fourth plate 81 includes a step 81b formed thereon. A width of the fourth plate 81 where the fastening part is formed thereon is smaller than a width of the plate where the step 81b is formed. The step 81b, which positions the inverter 90, together with the bracket 80 and the inverter 90, will be described in more detail below.
The fastening part comprising the second plate 84 extends from the fourth plate 81 to a height which is lower than the height at which the first plate 82 extends from the fourth plate 81. In addition, one end 84b of the second plate 84 is bent at a right angle in a direction of the first plate 82 thereby creating a ‘’ form.
The second plate 84 of the fastening part also has a fastening hole 84a for fastening a screw (not shown). The screw allows for rigid fastening of the inverter 90 to the top case 70. The first plate 82 includes two face tape 85 on an outside surface of the first plate 82 that also fastens the inverter 90.
A process for fastening the inverter 90 to the related art bracket 80 will now be described.
After inserting the inverter 90 between the fastening part comprising the second plate 84 and the first plate 82 with the inverter 90 slanted, the inverter 90 is pushed to where the step 81b is formed. When an end of the inverter 90 is positioned at the step 81b, a middle section of the inverter 90 is seated on the first plate 82. In this instance, a cover paper covering the two face tape 85 adhered to the first plate 82 is peeled off, such that the inverter 90 attaches to the first plate 82 with the two face tape 85.
FIG. 3 illustrates a perspective view of the inverter 90 fastened to a related art bracket 80.
Referring to FIG. 3, once the inverter 90 fastens with the first plate 82 and the two face tape 85, the plates 81, 82, and 83, surround upper and lower ends of the inverter 90, thereby securely holding the inverter 90.
A screw is then inserted in the fastening hole 84a in the second plate 84 of the fastening part, thereby fastening the inverter 90 with the bracket 80.
However, the related art bracket has the following problems.
First, the use of two face tape for fastening the inverter to the bracket requires the cumbersome task of peeling the cover of the two face tape in order to attach the inverter with the bracket.
Second, the attachment of the inverter to the bracket with the two face tape makes detachment of the inverter for inspection and the like inconvenient, and is liable to damage the inverter during detachment.